Olympus-OM
[Top] [All Lists]

[OM] Re: Apertures, where is f22 ?

Subject: [OM] Re: Apertures, where is f22 ?
From: Winsor Crosby <wincros@xxxxxxxxxxx>
Date: Tue, 07 Jun 2005 13:16:03 -0700
In lenses for the 35mm film format you start running into significant  
softening of the image  by F16 due to diffraction effects of the  
physical size of the aperture. It just gets worse at F22. In smaller  
format digital cameras the cutoff is frequently before F8, for the  
same reason. The newer Sony digital cameras have been roundly  
criticized because their exposure program goes immediately to a small  
F stop and has soft images as a result. I think leaving it off is  
just a recognition that knowledgeable photographers, who seem to be  
the only people still using lenses with F markings, just don't use  
F22 because of image quality issues.

Just for your own information you could check out the lens tests at  
Gary Reese's web site and see the resolution start to drop at F16 in  
lens after lens.



Winsor
Long Beach, California, USA




On Jun 7, 2005, at 12:53 PM, Der Eiserne Reiter wrote:

> List,
>
> let me offer a new technical subject:
>
> I have often wondered why some lenses in the 28-50mm focal range do
> not offer an additional f stop. I understand that is is technically
> difficult to provide both wide and small apertures, and good bokeh,
> but for landscape photography, f22 is very helpful sometimes.
>
> Why do some lenses stop at f16 and others continue to f22 ? Do other
> people care about f22 ? For instance, the 50/3.5 features f22, while
> the 1.2, 1.4, 1.8 do not.  Technically it is feasible to get f22 with
> a wider lens, as was demonstrated by C*non in the 50s with their
> 50/1.2 lens. Why do the 35/2.8, 28/3.5 and 28/2 not have f22 ?
>
> Just wondering,
>
> Roland.
>
> PS: forgive my English, it's my third language. As our Kahlifonian  
> governor says:
>     Q: isn't my English very good - A: yes it isn't ...
>
>
>
>
> FeRider (R.)
>
>
>
> __________________________________
> Discover Yahoo!
> Stay in touch with email, IM, photo sharing and more. Check it out!
> http://discover.yahoo.com/stayintouch.html
>
> ==============================================
> List usage info:     http://www.zuikoholic.com
> List nannies:        olympusadmin@xxxxxxxxxx
> ==============================================
>


==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz